Iran trumpeted advances in nuclear technology on Wednesday, citing new uranium enrichment centrifuges and domestically made reactor fuel, in a move abetting a drift towards confrontation with the West over its disputed atomic ambitions.

The announcement underlined Iranian determination to pursue a nuclear program its Islamic clerical rulers see as a pillar of power, protection and prestige despite Western sanctions that are inflicting increasing damage on Iran’s oil-based economy.

Iran has been resorting to barter to import basic staples as sanctions, imposed over its pursuit of nuclear activity seen in the West as geared to developing atomic bombs, have spread to block its oil exports and central bank financing of trade.

Tehran has for some years been developing and testing new generations of centrifuges to replace an outdated, breakdown-prone model. In January it said it had successfully manufactured and tested its own fuel rods for use in nuclear power plants.

The aim of its announcements on Wednesday was to show that international sanctions are failing to stop it making progress in nuclear know-how despite trade embargoes and to strengthen its hand in any renewed negotiations with six world powers.

“The fourth generation of domestically made centrifuges have a higher speed and production capacity … It will be unveiled on Wednesday,” state television said, without giving a source.

It was the latest display of Iran thumbing its nose at a series of UN resolutions demanding that it suspend uranium enrichment and open up to UN nuclear inspectors.

Last year, Iran installed two newer models for large scale testing at a research site near the central town of Natanz. But it remains unclear whether Tehran, subject to increasingly strict trade sanctions, has the means and components to make the more sophisticated machines in industrial quantity.

If Iran eventually succeeded in introducing modern centrifuges for production, it could significantly shorten the time needed to stockpile enriched uranium, which can generate electricity or, if refined much more, nuclear explosions.

Tehran has worked for several years to perfect faster, more reliable centrifuge machines than the 1970s-vintage P-1 model it now uses to refine uranium.

Western analysts were skeptical of the proclaimed advances.

“We have seen this before. We have seen these announcements and these grand unveilings and it turns out that there was less there than meets the eye. I suspect this is the same case,” said Shannon Kile at the Stockholm International Peace Research Institute (SIPRI).

NO CHANGE OF COURSE

The United States and Israel have not ruled out military action if diplomacy and sanctions are ultimately judged futile in reining in Tehran’s nuclear activity.

Iran has threatened retaliation for any attack or effective ban on its oil exports, suggesting it could seal off the main Gulf export shipping channel, the Strait of Hormuz, used by a third of the world’s crude oil tankers.

A senior Iranian official said Iran would load domestically made nuclear fuel rods into its Tehran Research Reactor on Wednesday for the first time to keep it running.

“The first home-made nuclear fuel rods will be loaded in the Tehran Nuclear Research Reactor in the presence of the president,” Ali Baqeri, deputy head of Iran’s Supreme National Security Council, told ISNA.

The Tehran reactor produces radio-isotopes for use in medical treatments and agriculture.

Iran says it was forced to manufacture its own fuel for the Tehran reactor after failing to agree terms for a deal to obtain it from the West to replenish imported Argentinian stocks that will run out in the near future.

In 2010, Iran alarmed the West by starting to enrich uranium to a fissile purity of 20 percent for the stated purpose of conversion into special fuel for the Tehran reactor.

In boosting enrichment up from the 3.5% level suitable for powering civilian nuclear plants, Iran moved significantly closer to the 90% threshold suitable for the fissile core of a nuclear warhead.

“Another achievement to be unveiled today is the inauguration of a project of producing 20% enriched uranium at the Natanz facility, as well as producing 20 percent fuel plates,” state television said.

Analysts remained doubtful that Iran would be able to operate the research reactor with its own special fuel.

“As usual, the announcement surely is exaggerated.

Producing the fuel plates … is not so hard. But the plates have to be tested for a considerable period before they can be used safely in the reactor,” said Mark Fitzpatrick of London’s International Institute for Strategic Studies.

“If Iran is really running the reactor with untested fuel plates, then my advice to the residents surrounding the building would be to move somewhere else. It will he unsafe.”

Spent fuel can be reprocessed into plutonium, the alternative key ingredient in atomic bombs. But Western worries about Iran’s nuclear program have focused on its enrichment program, which has accumulated enough material for up to several bombs, in the view of nuclear proliferation experts.

Analysts say the fuel rod development itself will not put Iran any closer to producing nuclear weapons, but could be a way of telling Tehran’s adversaries that time is running out if they want to find a negotiated solution to the dispute.

The most recent talks between world powers and Iran failed in January 2011 because of Tehran’s unwillingness to discuss transparent limits on enrichment, as demanded by several U.N. Security Council resolutions passed since 2006.

But Iran said recently it is ready to hold fresh talks with no preconditions. “We will also a reply to the EU’s foreign policy chief [about nuclear talks] today,” Baqeri said.

An earlier version of this story reflected information from Iran’s English-language Press TV indicating Iran would be cutting off oil exports to six EU countries. The story has been adjusted to reflect Iran’s official denial of those reports.